Clamping-jack.



CLAMPINGr-JACK.

Specicaton of Letters Patent.

Patented July 16 1912.

Application filed. April 22, 1912. Serial No. 692,491.

To all whom t may concern: Y

Be it known that l, 1WILLIAM; LEE GRANT, a citizen of the United States, residing at Norfolk, in the county of Madison and State of Nebraska, have invented certain new and useful Improvements in Clamping-Jacks, of which the following is a specification.A

This invention relates to an improved clamping-jack, useful particularly in preparing or forming shims in bridge repair work; and it has for its object to provide a portable device, preferably constructed of metal, by means of which large and heavy blocks may be rigidly held and supported while being sawed. The device is also useful for other purposes, where heavy objects are to be securely held or sustained in an elevated position.

The invention consists of the novel con-` struction, combination and arrangement of parts as described herein and claimed, and as illustrated in the drawing, wherein,

Figure 1 is a front view, partly in section, of the device. y Fig. 2 is a sectional view on line 2 2 of Fig. l. Fig. 3 is a rear view, partly broken, of the device. Fig. 4 is a plan view of the same.

Referring to the drawing for a more particular description, numeral 5 indicates a flatplatform, this being preferably an integral structure and consisting of the straight bar or plate 6 for the front of the platform, and the rearwardly extending segmental bar or plate 7. Angular recesses 8 are formed to open upon the bottom of the platform at or near the junction of the straight bar or plate 6 and the segmental bar 7, and a simi lar recess 9 is formed in`and at substantially the middle of the segmental part of the platform.

At 10 are indicated comparatively small apertures of angular form opening upon recesses S and 9, and upon the upper face of the platform; the recesses and apertures thus formed provide bearings or sockets for the legs 11, 12 and 13. The legs are prcfcrably formed with tapered lower terminals 14;, their upper terminals being provided with projections 15, and the projections and upper parts of the legs are of such form that they substantially fill the recesses and apertures within which they may be mounted, and when desired, the legs may be readily removed from the platform.

Upon the inner side and between the ends of leg 11 is rigidly mounted, in any suitable manner, the clamping-member 16. At 17 are shown a pair of operating-screws or threaded crank-shafts. At 18, adjacent to clamp 1G, is indicated a second clampingmember formed with recesses 19 opening upon its inner side. Shafts 17 are mounted upon member 16, but are conveniently removable therefrom, their inner ends which traverse said member being secured by keepers 20 disposed wit-hin recesses 19; and the shafts are provided with collars 21 adapted to bear upon the outer side of member 1S. The cranks of members 17, preferably, are provided with handles 22 and these members have threaded connections with leg 12.

It will be understood that by manually rotating members 17 clamp 18 may be forcibly moved toward member 1G for engagement between the clamping-members of any object, as a block of wood or other material, or that clamp 1S may be moved in a reverse direction for the release of such object; and it will be seen that the weight of the object thus held or sustained will be adequately supported by the device, the clamps and threaded shafts being normally disposed in the vertical plane of the front plate 6 of the platform and between the front legs 11 and 12.

ln order that the combined weight of the clamping-member 1S and the cranks carried thereby may be adequately sustained, and to prevent binding of the contacting, threaded parts of the screws with the leg 12 while this clamping-member is moving under operation of the cranks, a carrier is provided for these parts consisting of the supporting-arm or link 23, said arm being provided at its upper terminal with the roller-member or wheel 21 adapted to move upon trackway 25, this trackway being disposed parallel with the platform and with the threaded shafts 17, and provided with a vertical flange or guard 26 extending a part of the distance between the ends of the trackway. Since it is desirable that the trackway may be mounted upon the flat, front side of plate 6, the threaded shafts or screws being normally in the vertical plane of said plate, the upper part of arm or link 23 is formed angular to project below the trackway as shown in Fig. 2, so that the carrier may move freely upon said trackway.

In operation, when the cranks are manually rotated, clampingmember 18 will be moved horizontally, and the weight of the movable parts mentioned will be sustained by the trackway.

The device provides avery useful articlev in connection with bridge-repair work, where timber must be securely clamped and held above the ground while the shims are cut therefrom, by use of a saw; also, since the parts may be readily disconnected, the device may be conveniently moved from one place to another.

The parts may be readily assembled, and when the device is disposed upright as shown in the drawings, the tapered ends enter the ground in a: manner to resist strains occasioned by the screws and to prevent undue vibrations.

To disconnect the parts so that the device may be conveniently moved or transported, the platform may be lifted or elevated from the legs after the wheel has been disengaged from the guard. Terminal 27 of theV guard is located at a suitable distance from the recess 8, within which leg l2 is inserted, to permit the removal of the wheel from the guard before the platform Vhas been'disconnected; or the carrier may be disconnected by causing the clamping-member 16 to be moved in a direction opposite to leg 12, leg 1l being first removed to permit this operation.

The clamping members may be formed with a rugose surface as shown in Fig. 2 so that the timber blocks or other objects may be securely held therebetween.

On account of the upper terminals of the legs being angular or square, in cross-section, the threaded shafts and clampingmembers when the parts are assembled, will be maintained in alinement, substantially, and the inner faces of the clamping-members will be maintained parallel with reference to each other.

Having fully described my' invention, what l claim and desire to secure by Letters Patent is,-

l. A clamping-jack comprising, in combination, a platform provided with a trackway having a guard, and provided with recesses; supporting-legs adapted to be nonrotatively and removably mounted adjacent to each other in said recesses; a clampingmember mounted upon one of the supporting-legs; a pair of shafts formed with cranks, each having a terminal portion formed as screws for a threaded connection with an adjacent supporting-leg, the opposite terminals of the shafts being connected with the second clamping-member; a rollermember adapted to be removably mounted upon said trackway inwardly of the guard; and a link extending between and mounted upon the roller-member and the second clamping-member.

2. A clamping-jack, comprising a platform provided with supporting-legs and with a trackway; a stationary clampingmember; a second clamping-member, a pair of crank-shafts rotatively mounted therein and having a threaded connection with one of the supporting-legs; a carrier upon said trackway connected with the second clamping-member; the rot-ation of the crankshafts causing a movement of the second clamping-member in the horizontal plane of the stationary clamping-member.

3. A clamping-jack, comprising a platform formed with angular recesses; legs formed angular in cross-section at their upper ends for removable mountings in said angular recesses; a clamping-member rigidly mounted upon one of said legs; a second clamping-member adapted normally to have horizontal movements in the plane of the stationary clamping-member, and a carrier adapted to be disposed upon the platform and connected with the second clamping-member.

1L. In devices for the purpose described, the combination of a platform provided with legs disposed adjacent to each other and having tapered lower terminals for engaging in a support; a first clamping-men ber rigidly mounted upon one of said legs; a second clamping-member mounted upon an adjacent leg; means to move the second clamping-member in a' direction of the first clamping-member, said movement normally tending to direct stresses outwardly of the legs upon which the clamping-members are mounted, the engagement of the tapered lower terminals of said support tending to resist said stresses.

5. A clamping-jack, comprising a platform provided with supporting-legs and a trackway; a stationary clamping-member; al second clamping-member provided with recesses; a pair of crank-shafts provided with collars, said shafts having a threaded connection at oneof their terminals with one of the supporting-legs, their opposite terminals being disposed within said recesses with their collars bearing adjacent to the recesses upon said second clamping-member; a carrier upon said trackway connected with said second clamping-member; said crankshafts being rotatable for causing movements in alternation, in directions toward or opposed to the stationary clamping-member.

In testimony whereof I have aiiXed my signature in presence of two witnesses.

VILLIAM LEE GRANT.

Witnesses:

MARTIN VEYENBERG, VILLIAM L. KENNVEY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. c. 

